X-ray photographic apparatus



4 Shuts-Sheet. 2

b wen M W -J'. R. KELLEY Filed Feb. 21.- 1925 X-RAY PHOTOGRAPIIIC-APPARATUS July 1, 1930.

9 C 716 flftorney 7 I 3 ll: r l w \w m u: -w Wm II =u lll lnl l Z 5 WMT. u! v m J.- A: n 2 I 7 I11 I7 L I Ill 3 u l-In'll I I l I i l I II'llllllll 4. v z m 6 7 W 1 a. 57 3 0 7 3 5 8 no 6 3 n/ MI &0 7 -1 6 1 7M u July 1, 1930. KELLEY 1,768,769

X-RAY PHOTOGRAPHIC APPARATUS Filed Feb. 21. 1925 4 Sheets-Sheet 3Inventor 1 e W m fl y .50

Patented July 1, 1930 STATES rarer trio X-RAY .HoToGRAPHIo APPARATUSApplication filed February 21, 1925. Serial No. 10,961.

My invention relates to improvements in apparatus for taln'ng X-rayphotographs. One of its'object's is to provide improved apparatus tosupport the X-ray tube and the subject to be photographed with referenceto the sensitive plates. Another Object is to provide in combinationwith an X-ray tube a reversible table to support both the sensitiveplate and the subject to be photographe'd Another object is to providefor X-ray purposes an improved plate holder and movable ray interceptingdiaphragm. Another object is to provide an improved plate holder withmovable ray intercepting diaphragms upon opposite sides ofthe plateholder. Another object is to provide an improved combination ofreversible table and plate holder adjustable thereon. Another object isto provide improved means to adjust and lock the reversible table andplate holder. Another object is to provide improved means to feed theBuckey diaphragm or diaphragms with reference to the sensitive plate.Another objectis toprovide 1 improved means to time and feed the Buckeytdiaphragm and to energize the X-ray tube in synchronism. Another obj ectis to provide improved means whereby the rate of feed of the diaphragmmay be selectively varied. Another object is to provide improved meansto set, feed, and release the diaphragm. My invention also comprisescertain details of form and combination and arrangement of components,

all of which will be fully set forth in the description of theaccompanying drawings, in which: I

I Fig. l is a perspective view of an. X-ray tube and photographic tableembodying my invention. I I I I Fig. '2 is a plan ofthe apparatus shownin Fig. 1; I I

Fig. 3 is an enlargedsectional detail of means employed to lock thetable to its tached from the table.

Fig. 6 is an end view of the same. Fig. 7 is a front elevation ofFi'g'.5. Fig. 8 is a perspective view of the apparatus employed to latch andrelease the diaphragms, and to synchronize the movements of thediaphragnis with the development of X-rays in the tube. Fig. 8 is asectional detail of the fee speed controlling mechanism. 7

Fig. 9 is a wiring diagram showingthe electrical connections forsynchronously releasing the diaphragms and passing a current through theX-ray tube. I

Fig. 10 is an enlarged sectional detail of a portion of the latching andreleasing means shown in Fig. 8. v

Fig. 11 is a sectional detail showing the means employed to adjustablymount the plate holder and diaphragms with reference to the reversibletable.

Fig. 12 is a perspective view of a feed reversing cam employed tocontrol the movements of the diaphragms I Fig. 13 is a diagramillustrating the normal use of an X-raytube, a subject to bephotographed, and a plate holder and using the curved diaphragm.

Fig. 14.- is a view similar to Fig. 13 showing the normal use of a planediaphragm.

Fig. 15 is a diagram illustrating one position' of adjustment of thetube, and plate holder in which the plate holder is vertically beneaththe tube center. I I

Fig. 16 is a diagram similar to Fig. 15

illustrating relatively different positions of adjustment of the tubeand plate holder, employed for instance to secure a photograph of aninternal organ which if taken in position Fig. 15 would be in line witha bone or other opaque object.

The accompanying drawings illustrate the preferred embodiments of myinvention in which 15 represents a rectangular metal table frame havingjournal boxes 16 at opposite ends in which are journaled trunnions 17upon which the table or table top 18 is rotatably mounted so as to bereversibly adjusted relative to said frame.

A pin or stop roller 19 engages the frame 15 at opposite limits of theadjustment of the table top, and latch pins 20 projecting throughlongitudinal slots in the side of a tubular frame member 21 serve toengage recesses 22 in one or other of the forked brackets 23 carried byand at opposite sides of the table top to rigidly lock the table top tothe frame 15 at opposite limits of the table top adjustment. The latchpins 20 are carried by sleeve members 24, see Fig. 3. which are rigidlymounted upon a rod 25 extending through the tube 21 and provided atopposite ends with disks or knobs 26.

Springs 27 coiled about opposite ends of the rod 25 serve to resilientlyhold the pins 20 in the slots 22. It will be found convenient for anoperator wishing to reverse the position of the table to press his legagainst the knob 26 at either end of the table and with both hands freeto turn the table top over, and u on releasing pressure on the knob, theta le top will be automatically latched in position. The faces of thebrackets 23 are beveled so as to also serve to throw the thereon to andfrom the column 28. X-ra tube is also adjustably mounted upon latch pins20 to one side as the table is reversed should pressure on the knob 26be released before the pins 20 have entered the recesses 22.

A vertical tubular column or standard 28 is mounted by means of a seriesof rollers 30 to travel endwise along the tubular sections 21 and 29 ofthe table frame. Above the table is a horizontal bracket or frame 31,mounted by means of rollers 32 to travel vertically upon the column 28.The weight of the frame 31 is counterbalanced by means of a weighttraveling up and down within the column 28 and connected by means of achain 33 passing over a pulley 34 with the frame 31. An X-ray tube 340is adjustably mounted upon the frame 31 to travel The the rame 31 orrelative to the column 28 so as to have a substantially universaladjustment relative to the frame 31 or column 28 to enable the tube tobe inclined to various degrees, and at a variety of positions ordirections of inclination, to enable the X- rays to be directedtherefrom toward the table in substantially any desireddirection, as forinstance to direct the X-rays upon any desired internal organ and toavoid interposing bones or other more opaque objects in the path of therays to thereby obscure the photographic image. Independent lockingmembers are provided to lock the column 28 to its adjusted position uponthe table frame, to lock the frame 31 to its adjusted position upon thecolumn 28, and to lock the X-ray tube to its adjusted position upon theframe 31.

The table top has a channeled face 35 and a plane face 36 spaced apart asufficient distance for the plate holder and diaphragm apparatus to beinterposed between said respective table faces, and to be ad justedtherein endwise of the table either in conjunction with the column 28and X-ray tube carried thereby or independently of said column and tube.The material of which the table faces 35 and 36 are constructed ispervious to X-rays, to enable sensitive plates carried in the plateholder between the table faces 35 and 36 to be exposed to the influenceof X-rays passing from the X-ray tube through the subject to bephotographed when supported upon the table top, through the table topface, through one of the diaphragms and through the face of the plateholder to the sensitive plate therein.

The diaphragms and plate holder apparatus comprise a supporting frame 37which is supported within a recess between the two faces and 36 of thetable top, preferably by means of a series of rollers 38 engagingopposite sides of a pair of guide rods 39 carried by and at oppositesides of the table top whereby the frame 37 is movable to variouspositions of adjustment longitudinally of the table. Guide channels 40and 41 are provided centrally within the frame 37 to receive and guide aphotographic plate holder into a central position within frame 37. Onone side of the plate holder within the frame 37 is mounted a curveddiaphragm 42 fitted closely to the inner side of the curved table face35, and curved substantially to the arc of a circle with the target ofthe X-ray tube as a center. On the opposite side of the plate holderwithin the frame 37 is another diaphragm 43 having a plane face andclosely fitted to the inner side of the table face 36. The respectivediaphragms are composed of alternate relatively narrow strips ofmaterial which are respectively pervious and impervious to X- rays andare designed to intercept stray rays, that is rays which are nottraveling in nearly parallel directions, and to thereby facilitate theproduction of more sharply defined shadowgraphs than would be otherwiseobtainable. In order to prevent the dlaphragms from producing a ribbedeffect upon the sensitive plates, said diaphragms are kept in motiontransversely across the face of the sensitive plates, during the periodof exposure of the plates tothe X-rays.

In order to move the diaphragms 42' and 43 they are connected togetherso as to'move in unison. The curved diaphragm is guided at oppositesides thereof by means of rollers 440 traveling in curved slots 44carried by the frame 37. The diaphragm 43 is similarly supported byroller 450v traveling in straight guides 45 carried by the frame 37.Energy to move the diaphragms relative to the frame 37 and theplateholder carried thereby .is provided by means of a shaft 46 mountedin a stationary tubular barrel 47 and connected to said barrel-by meansof a coiled spring 470 attached at one end to the shaft 46;and at itsopposite. end to the barrel 47. The shaft 46 is journaled at oppositeends to the frame 37 and is provided with a cam 48 at one end, to whichcam one end of'a steel ribbon49 is attached. The opposite end of theribbon 49 is attached to the face of a pulley segment 50 which ismounted rigidly upon a shaft 51. One end of the shaft 51 is journaled tothe frame 37, whilethe opposite end thereof is journaled in the endwalls of a chambered member 52 which contains a body of liquid and isprovided with. a stationarily mounted gate or partition 53, and with amovable vane or wing 54 mounted rigidly upon the shaft 51 to rotatetherewith within the cylindrical chamber of member 52. .The gate orpartition 53 has a port 55 controlled by a ball valve 56, which allowsthe fluid inthe chamber to flow in one direction only through port 55from one side to the other of the gate 53. A port 57 through the gate 53is variably controlled bytheadj'ustment of a manually operable valve 58to permit a relatively slow or rapid flow of the fluid from one side tothe other of the gate 53 in a direction opposite to the flow through theport 55. The barrel 47 be manually rotated to put any desired tensionthrough the spring 470 upon the shaft 46. A pawl 59 attached to theframe 37 engages a ratchet wheel 60 on one end of the barrel 47 to ioldsaid barrel to its adjusted positions. The liquid in the chamberedmember 52 is driven by the vane 54 alternately in opposite directionstoward the gate 53 as the shaft 51 is rotated in opposite directions. Inone direction, that is to reset the diaphragms in position to be fedforward, the liquid flows freely through the port 55 allowing thedia'phrag'ms to be quickly returned to operative position, and latchedready to be released to feed forward. When the shaft 51 rotates in theopposite direction to feed the diaphrag ns for a radiographic exposure,the liquid of chambered member 52 flows through the port 57 which stud63 is adapted to be disengaged from the projection 62 to allow thediaphragms to feed forward either by rocking the shaft so as to free thestud 63 from projection 62, or by shifting the shaft 65,, crank'arm 64,andstud 63 endwise of shaft 65 to free the stud 63 from the projection62. To manually release the stud 6.3 from the projection 62 I preferablyemploya spring actuated plunger 66 to normally engage the crank arm64and prevent a disengagement of the stud 63, and a ball 67 and chain 68to be manually operated to retract the plunger 66 against the action ofthe spring 69.

Vfhere it is, desired to release the stud 63 from the projection 62 byelectrically actua'ted', means in 'synchronism with the application ofenergy to'the X-ray' tube, I providean electro-magnet or solenoid 7O'having a pull rod 71 whichhas an annular recess 72 to be engaged bythe periphery of. a diskr73 mounted upon the end of shaft 65 wherebywhen the solenoid is energized electrically the pull rod 71 pulls" theshaft 65 endwise toward the solenoid 70 against the action of a spring74coiled upon and tending to force the shaft 65 away from the solenoid 70.The endwise movenrentv of shaft 65- carries with it the crank 64 andstud 63,. thereby releasing the stop 62 from the stud 63 and allowingthe segment 50and shaft 51 to rotate at the predetermined rate of speedprescribed by the adjustment of the valve 58" and port 57, and allowingvthe shaft 46 and spring 470 to feed the diaphragms forward acrossopposite faces of the plate holder at the prescribed rate of speed. Thestem of the valve 58 is provided" with a pointer 76 which moves over theface of a scale 77 on the face of frame 37 and thereby enables theoperator to set the valve 58 to provide for any desired rate of travelof the diaphragms.

It is desirable that the movement of the diaphragmsand the'applicationof energy to the X-ray tube be synchronized so that by the closing of anelectrical circuit the diaphragms will first be released and coinmencetheir movement relative to the plate holder, at a predetermined rate ofspeed depending upon the nature of the photograph to be taken and thelength of exposure to be given, then that current shall be applied tothe X-ray tube for the predetermined length of time considered requisitefor the exposure, and then the current cut off from the X-ray tube, andlater that the forward feed of the diaphragms be automatically sto pedand the energizing circuit opened, an finally that the diaphragms andtheir feeding apparatus may be reset or returned to their originalposition without applying energy to the X-ray tube.-

In order to accomplish these features in synchronism I provide anelectrical three wire circuit substantially as shown in Fig. 9 havin forinstance two positive branches 78 and 79, and a negative or return line80. A push button 81 located at any position in the circuit convenientto the operator, enables the circuit to be closed when conditions aresuitable for taking the photograph, to thereby initiate the sequence ofmovements and stops heretofore outlined. The closing of the circuit atthe push button 81, serves to energize the solenoid 70, to move theshaft 65 endwise thereby retracting the latch member starting theforward feed of the diaphragms, which also causes the shaft 51 torotate. The shaft 51 carries a switch blade 82 which is in engagementbetween two electrical contacts83 and 84. After the latch 63 has beenreleased blade 82 rotates to open circuit 78. When shaft 51 commences torotate it thereby furnishes means for later closing the circuit 7 9 andelectrically actuatin a switch 840 to close the primary electricalcircuit 85 of a high tension transformer, the secondary 86 of whichfurnishes electrical energy to the X-ray tube 340 so long as the switchblade 89 continues to close the circuit 79 at the contact points 91 and92. During theperiod while circuit 78 has been closed at the points 83and 84 by the blade 82,and subsequent to the closing of the circuit atpush button 81, a cam 87 also mounted rigidly upon and rotatable withthe shaft 51 moves into position to engage a stud 88 projecting from anendwise movable switch member 89 which is resiliently energized by acoiled spring 890 in opposed relation to a coiled spring 891 to normallyhold the member 88 in the path of the cam 87 and the member 89 out ofengagement with the electrical contacts 91 and 92 interposed in theelectrical circuit 79.

As the shaft 51 rotates the cam 87 compresses spring 890 and throws theswitch member 89 into engagement with the contacts 91 and 92 therebyclosing the circuit 79, which occurs for instance after the diaphragmshave made approximately one-fifth of their movement. Closing of thecircuit 79 serves to electrically energize the switch 840, which in turncloses the primary circuit 85, and energizes the X-ray tube. The periodduring which the X-ray tube is energized covers for instanceapproximately threefifths of the period of movement of the diaphragms,leaving the diaphragms still in movement for approximately one-fifth oftheir period of movement after the circuits 79 and 85 have been openedand the X-ray tube deenergized. The circuit 79 is opened due to the cam87 passing out of engagement with the stud 88 allowing the spring 890 toretract the switch member 89 from the contacts 91 and 92. Opening ofcircuit 79 releases the electrically controlled switch 840 to therebybreak the primary circuit 85. The rotation of shaft 51 also shiftsswitch lever 82 out of engagement with contacts 83 and 84 releasing theshaft 65 from the pull of the solenoid and allowing the latch member 63to move endwise into position to again engage the stop or projection 62of the segment 50. a

When the diaphragms have reached the limit of their movement relative totheir supporting frame and travel guides 44 and 45 thereon, thediaphragms come to a rest, and require to be reset to become againoperative. This resetting operation is effected by manually rotating theshaft 51 in a reverse direction by means of a hand lever 94 attached tothe shaft 51 outside of the frame 37. Movement of the shaft 51 inreverse direction to reset the diaphragms causes the fluid in thechambered member 52 to flow freely past the ball 56 through port 55ahead of the vane 54. At the same time the stud 88 which normally standsin the path of the cam 87 is engaged by the inclined edge 95 of said camto thrust the stud 88 in a reverse direction to that of the forward feedof said cam, thereby preventing the circuit 79 being closed at thecontacts 91 and 92, and thus preventing the Xray tube being energized onthe reverse or resetting movement of the shaft 51. As soon as the stop62 of segment 50 reaches and engages the latch member 63, the diaphragmsare reset in 0 erative position ready to repeat the cycle of movementheretofore described.

I preferably provide an alarm bell or similar member 97, the hammer 98of which is adapted to be tripped by a stud 99 carried by and rotatablewith the shaft 51 to indicate to the operator when the diaphragms havereached the limit of their movement, and are ready to be reset.

Where for instance it is desirable to secure a comprehensive radiographof the whole or major portion of the chest or abdomen, corr sponding toa view in ordinary photography with a wide angle lens it is preferableto support the subject 101 upon the channeled face 35 of the table andmake the exposure upon a relatively large sensitive plate through thechanneled diaphragm 42 as indicated diagrammatically in Fig. 13. Where,however, it is desired to photograph a single organ 103 or restrictedportion of the chest or abdomen, for instance, it is preferable tosupport the subject to be radiographed uponthe planetable face 36andmake theexpos'ur'e through the plane faced diaphragm 4C3 uponarelatively smallfsen'sitive platelas indicated in Fig 14. In Fig. 15 Ihave 'i'lliistrated dia-grammatically one 'adjustment of the subject-101upon the table face and above a sensitiveplate 1G2 in'orde'r that anorgan 103,;for instai1ce may be radiographed to'obtain a plate fullofd'et'ail Without interference reason of 8 adj acently positioned bonesor other dense or nearly opaque objects 104:. *In'Fig. 15"I-haveillustrated' diagrammatically another relative adjustment of the X raytube, 'thesubject 101, and the plate holder anddiaphragm,

somewhat similar to that shown in 15,

illustrating the range of adjustment of said members for obtaining"similar results to those above specified for -1 ig.

The apparatus illustrated particularly in Fig. 8* for regulating therate of movement of the diaphragms avoids any "sudden jump or vibrationof the diaphragms when the latch members 62 and 63 are released,- andcauses the diaphragms to commence movement without vibration; to quicklyreach maximum rate of' speed and thereafter to maintain a uniform rate*of speed until the diaphragms reach the limit of'their movement's, atwhich time the exposure has been fully completed, and any vibration instopping the diaphragm movement is not liable to afiect the image onthesensitive plate. It will be noted that the length of exposure of thesensitive plate to X-rays depends upon the period of time taken by thecam 87 to pass the stud 88, and that as the cam 87 is carried by theshaft 51, regulation of the valve 58 the "position of which isaccurately shown by the pointer 76 on a scale'77,fenables the operatorto regulate the speed of the diaphragms and the length of exposure ofthe sensitive plate at one operation by adjustment of said valve '58,and that the period of exposure "of'the plate maybe predetermined andread directly from the scale 7 7, The respective diaphragmsare jointlyattached by means of ajclamping member 106to the metal tape or strap 19.j g

In Fig. 4 I have illustrated a latch memher 107 seated in a socket 108attached to thediaphragm frame 3-7, acoiled spring 109 serves toenergize said latch member to latch the diaphragm framef37 mime 2 8,

to cause theframe 37 when desired to move endwiseof'the table withcolumn28 and X-ray tube carried by column-28. order that the frame 37may be latched with reference to the columr'r2'8 in a plurality ofpositions as for instance withthesensitiv'e plate directly beneath theX-ray tube as indicatedjin Fig. 15,61' either to the right hand or totheleft hand thereof as indicated in Fig. 16, Iprovide plurality-bfinchangaging "sockets 1'12 mounted and adjustable upon "a bar 114:carried'by the column 28,

whereby the latch member 107 may enter out of engagement with thesockets 112 when it is 'desired'to disengage the frame 87 from thecolumn 28and independently adjust the frame 37 by hand alongthe table.

The-apparatus herein shown and described is capable of considerablemodification within the scope of the claims without departing from thespirit of my invention. 7

What I claim is:

1. In combination with an X-raygenerator, a table frame, a table topreversibly mounted thereon and provided with a substantially plane tableface and a channeled table face to be selectively employed to supportsubjects'to be radiographed with referenceto said generator, a plateholder carriage mounted intermediate of said table faces and providedwith a substantially plane "movable diaphragm 'and'a channeled movablediaphragm'and an interposed sensitive plate holder. j 2. In combinationwith an X-ray-genera' tor, a'table frame, a table top reversibly mountedthereon and provided with a substantially plane table face and achanneled table face to be selectively employed to support subjects tobe radiographed with reference to said generator, said generator andtable top being relatively adjustable lengthwise of said table top, aplate holder carriage mounted intermediate of said table faces andadjustable endwise relative to said table top, said carriage beingprovided with a substantially plane movable diaphragm and a channeledmovable diaphragm and an interposed sensitive plate holder.

3. In combination with an X-ray generator, a table frame, a table topreversibly mounted thereon and provided with a substantially plane tableface pervious to X- rays and a channeled table face pervious to X-rays,a resiliently energized latch bar provided with a latch member andadapted'to be energizedby pressure on the end of's'aid' latch bar torelease the latch carried thereby from interengaging latch memberscarried at opposite sides of'said table top.

4. In combination with an X-ray generator, a table frame, a table topreversibly mounted thereon and provided with a substantially plane facepervious to "X-rays, and a "channeled face pervious to X-rays, saidtable top and generator beingr'elatifvely adjustable lengthwise of saidtable, "a sensitive "plate holder interposed be'tween said table faces,and'wlatch m chanism-tr; posi The latch :7 v

tively latch said table top to its adjusted positions relative to itssupporting frame.

5. In combination with an X-ray generator, a table frame, a table topreversibly mounted thereon and provided with a substantially plane facepervious to X-rays and a channeled face pervious to X-r'ays, said tabletop and generator being relatively adjustable lengthwise of said table,a plane diaphragm mounted to move across the inner side of said planetable face, a channeled diaphragm mounted to move across the inner sideof said channeled table face, a sensitive plate holder mountedintermediate of said table faces and said diaphragm and latch mechanismto positively latch said table top to its adjusted positions relative toits supporting frame.

6. In combination with an X-ray generator, a table frame, a table topreversibly mounted thereon and provided with a sub stantially plane facepervious to X-rays and a channeled face pervious to X-rays, said tabletop and generator being relatively ad- 'ustable lengthwise of saidtable, a plate older carriage interposed between said table faces andadjustable endwise of said table top, a sensitive plate holderdetachably mounted upon said plate holder carriage, means to selectivelylatch said plate holder carriage to said generator to cause saidgenerator and plate holder carriage to travel in unison lengthwise ofsaid table top, and latch mechanism to positively latch said table toptosubstantially opposite limits of its adjustment relative to itssupporting frame.

7. In combination with an X-ray generator, a table frame, a table topreversibly mounted thereon and provided with a substantially plane facepervious to X-r'ays and a channeled face pervious to X-rays, said tabletop and generator being relatively adjustable lengthwise of said table,a plate holder carriage provided with a plane diaphragm mounted to moveadjacent to said plane table face and a channeled diaphragm mounted'tomove relatively to said channeled table face, and adjustable endwise ofsaid table top, a sensitive plate holder detachably mounted upon saidcarriage intermediate of said diaphragms, means to selectively latchsaid carriage to said generator to cause said generator and carriage totravel in unison lengthwise of said table, and latch mechanism topositively latch said table top at substantially opposite limits of itsadjustment to its supporting frame.

8. In combination with an X-ray generator an electric circuit toenergize said generator, a plate holder supporting frame havin a recessto detachably receive a plate ho der, a diaphragm movably mounted uponsaid frame at one side of said plate holder to be interposed between theplate holder and a subject to be radiographed, means to drive saiddiaphragm across the face of the plate holder covering the period ofexposure of the plate, a latch to set and release said diaphragm, amember to open and close the primary of said generator energizingcircuit, a synchronizing electric circuit having a circuit closin switchand a circuit breaking switch, an partly controlled in unison with themovements of said diaphragm, said synchronizin circuit servingsuccessively to unlatch an initiate movement of said diaphragm, to closethe generator primary and excite the X-ray generator, to break thegenerator primary and deenergize the X-ray generator before movement ofthe diaphra m has ceased.

9. ln combination with an X-ray generator an electric circuit toenergize said generator, a plate holder supporting frame having a recessto detachabl receive a plate holder, a pair of diapl iragms movablymounted upon said frame at opposite sides of said plate holderrespectively to be interosed between the late holder and a subect to beradiograp ed, means to drive said diaphragms across the face of theplate holder covering the period of exposure of the plate, a latch toset and release said diaphragm, a member to open and close the primaryof said generator energizing circuit, a synchronizing electric circuithaving a circuit closing switch and a circuit breaking switch, andpartly controlled in unison with the movements of said diaphragm, saidsynchronizing circuit serving successively to unlatch and initiatemovement of said diaphragm, to close the generator primary and excitethe X-ray generator, to break the generator primary and deenergize theX-ray generator before movement of the diaphragm has ceased.

10, In combination with an X-ray generator, a plate holder supportingframe, a plate holder detachably supported by said frame, a diaphragmmovably mounted upon said frame to be interposed between said plateholder and a subject to be radiographed, means to drive said diaphragmacross the face of the plate holder, a member movable in unison with themovements of said diaphragm armed with a releasing latch member torelease said diaphragm and allow the diaphragm to move across the faceof the plate holder covering the period of the radiographic exposure,means operable by said movable latch member to close an X-ray tubeenergizing circuit after the commencement of movement of said diaphragmand to open said X-ray tube energizing circuit before movement of saiddiaphragm stops, means to control the rate of movement of said movablelatch carrying member, and a latch member operable to release saidmovable latch carrying member mes es.

and its latch to initiate movement of said diaphragm.

11. Radiographic apparatus comprising an X-ray generator, a reversiblesupport fora subject to be radiographed having a channeled face perviousto X-rays and a substantially plane face pervious to X-rays, a sensitiveplate interposed between said pervious supporting faces, a channeleddiaphragm interposed between said sensitive plate and said channeledpervious supporting face and adjustably mounted to move transverselyacross the face of said sensitive plate, a substantially plane diaphragminterposed between the sensitive plate and said plane supporting faceand adjustably mounted to move transversely across the face of saidsensitive plate, and means to feed said diaphragms across the face ofsaid sensitive plate.

12. Eaaiographic apparatus comprising an X-ray generator, a support forsubject to be radiographed pervious to X-rays, a sensitive plate locatedat the opposite side of said support from said X-ray generator, adiaphragm interposed between said support a d said sensitive plate andadjustably mounted to move transversely across the face of saidsensitive plate, a member under tension adapted to feed said diaphragmunder substantially uniform tension across said sensitive plate, a shaftoperatively connected. to said diaphragm to rotate in unison with themovements of said d1aphragm,

, a first latch member carried by said shaft,

a second latch member operable to release said shaft and diaphragm, achambered member in substantially axial alignment with said shaft andcharged with a fluid body and into which said shaft projects astationary gate between said shaft and the wall of said chamber, a bladewithin said chambered member carried by and movable with said shaft toinsure a substantially uniform rate of feed of said shaft and diaphragm,a valve manually operable to variably control the flow of a liquid insaid chambered member and thereby the rate of "ement of said shaft anddiaphragm, and means to release said first latch member from said secondlatch member.

13. li-adiographic apparatus comprising ir-ray generator, a support fora subject to be radiographed pervious to X-rays, a sensitive platelocated at the opposite side of said support from said X-raygenerator, adiaphragm interposed between said support and said sensitive plate andadjustably mounted to move transversely across the face of saidsensitive plate, a member under tension adapted to feed said diaphragmunder substantially uniform tension across said sensitive plate, ashaftoperatively connected to said diaphragm to rotate in unison withthe movements of said diaphragm, a first latch member carried by saidshaft, aisecond latch member operable to release said shaft anddiaphragm, adash-pot operatively connected to said shaft to. insure. asubstantially uniform rate. of feed of said shaft and diaphragm, a valvemanually. operable to variably control the fiow ofa liquid in saiddash-pot and thereby the rate of movement of said shaft anddiaphragm, anelectricalcircuit having an electrically actuatedswitch operable toenergize and de-energize said: X-ray generator, a circuit closing memberoperable by said shaft toenergize said X-ray generator through afraction of the period of rotation of said shaft, and means to releasesaid first latch member from said second latch member.

14. Radiagraphic apparatus comprising an X-ray generator, a support fora subject to be radiographed previous to X-rays, a sensitive platelocated at the oposite side of said support from said X-ray generator, adiaphragm interposed between said support andsaid sensitive plate andadjustably mounted to move transversely across the face of saidsensitive plate, means under tension to feed said diaphragm across saidsensitive plate, a shaft operatively connected to said diaphragm torotatably oscillate in unison with the movements of said diaphragm, achambered member charged with a body of fluid and into which said shaftprojects substantially axially thereof, a stationary gate extendingradially between said shaft and the wall of said chambered member, ablade carried by said shaft and oscillatorily movable in said chamberedmember to alternately drive said fluid in opposite directions therein, arestricted fiuid passage through said gate, a valve manually operable tovariably control said restricted passage and vary the rate of feed ofsaid diaphragm, a first latch member movable in unison with saiddiaphragm, a second latch member to engage said first latch member, andmeans to disengage said latch members and initiate a forward feed ofsaid diaphragm and said shaft.

15. Radiographic apparatus comprising an X-ray generator, a support fora subject to be radiographed, a sensitive plate located at the oppositeside of said support, a diaphragm interposed between said sensitiveplate and the support and adjust ably mounted to move transverselyacross the face of said sensitive plate, means under tension to feedsaid diaphragm across said sensitive plate, a shaft operativelyconnected to said diaphragm to rotate in unison with the movements ofsaid diaphragm, a chambered member substantially concentric with saidshaft and into which said shaft projects, said chambered member beingcharged with a substantially incompressible fluid, a stationary gateextending radially from said shaft to the wall of said chamber, arestricted fluid passage through said gate, a blade carried by saidshaft movable in said chambered member to drive said fluid through saidrestricted fluid passage, a valve manually operable to vary saidrestricted passage to thereby vary the rate of feed of said diaphragm,and latch members adapted to be disengaged to initiate a. forward feedof said diaphragm and speed regulating shaft.

In testimony whereof I have hereunto affixed my signature.

' JOHN ROBERT KELLEY.

